Problem: $\dfrac{9}{7} \div \dfrac{9}{8} = {?}$
Solution: Dividing by a fraction is the same as multiplying by the reciprocal of the fraction. The reciprocal of $\dfrac{9}{8}$ is $\dfrac{8}{9}$ Therefore: $ \dfrac{9}{7} \div \dfrac{9}{8} = \dfrac{9}{7} \times \dfrac{8}{9} $ $ \phantom{\dfrac{9}{7} \times \dfrac{8}{9}} = \dfrac{9 \times 8}{7 \times 9} $ $ \phantom{\dfrac{9}{7} \times \dfrac{8}{9}} = \dfrac{72}{63} $